SPECIES OF STREPTOMYCES 39 



Antagonistic properties: Usually none. Some strains produce actino- 

 mycetin. Some produce thiolutin or endomycin. 



Habitat: Universal occurrence in dust and soil. 



Remarks: Because of the universality of this species and the ease of its 

 superficial identification, numerous strains with varying physiological prop- 

 erties have been reported in the literature. 



2. Streptomyces longisporus (Krassilnikov) comb. nov. (Krassilnikov, 

 N. A., Actinomycetales, Akad. Nauk. USSR, Moskau, 1941, 47.) 



Vegetative growth: Colonies colorless. Some strains produce a brown 

 substance in protein media. 



Aerial mycelium : White. Sporophores long, with many curls, weak spirals, 

 occasionally forming small brooms. Spores cylindrical, with sharply cut 

 ends, 1.0-1.7 by 0.6-0.8 n; later spores may become oval, 0.9-1.0 by 0.5- 

 0.8 M . 



Gelatin: Liquefaction rapid. 



Milk: Coagulation and peptonization rapid. 



Starch: Hydrolysis strong. 



Cellulose: Growth fair to good. 



Nitrate: Reduction varies. 



Antagonistic properties: None. 



Remarks: Distinguished from Streptomyces albus in that its spores are 

 never spherical. 



3. Streptomyces globisporus (Krassilnikov) comb. nov. (Krassilnikov, 

 N. A., Actinomycetales, Akad. Nauk. USSR, Moskau, 1941, 48.) 



Vegetative growth: Colonies flat, colorless, not pigmenting medium. 



Aerial mycelium: Well-developed, powdery, white. Sporophores straight, 

 frequently forming brooms. Spores oval and spherical, 0.8 n in diameter. 



Synthetic agar: Growth good, giving flat, colorless colonies, not coloring 

 medium. Well-developed, powdery, white with trace of yellow. 



Nutrient agar: Colonies grayish, smooth or lichnoid; aerial mycelium 

 poorly developed. 



Potato: No aerial mycelium or trace; faint brown color of plug. 



Gelatin: Liquefaction rapid. 



Milk: Peptonization rapid; no coagulation. 



Starch: Hydrolysis slow. 



Cellulose: Growth good. 



Sucrose: No inversion. 



Antagonistic properties: None or weak. 



Remarks: Several substrains of this species were recognized on the basis 

 of milk coagulation, proteolysis, and pigmentation of aerial mycelium. 



